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Delitos en la bancarrota : aspectos penales de la Ley 20.720, sobre reorganización y liquidación de empresas y personasRamírez Araya, Juan Pablo January 2016 (has links)
Memoria (licenciado en ciencias jurídicas y sociales)
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Total Synthesis of Bio-active Natural Products Gabosines, Crassalactone C, Anamarine and Iriomoteolide 3aKumar, S Mothish January 2014 (has links) (PDF)
First chapter of the thesis describes the desymmetrization of the bis-dimethyl amide 1 derived from tartaric acid with vinyl Grignard reagents and subsequent reduction of the resultant -keto amides 2a-c to the -hydroxy amides 3a-c. Application of the -hydroxy amides 3a-c in the total
synthesis of bio-active natural products such as gabosines, crassalactone C and anamarine is described in the subsequent sections. In section A of the first chapter, application of the -hydroxy amides 3a-b to the total synthesis of gabosine A 4, gabosine F 5 and gabosine H 6 was described. Key strategy in the synthesis was the use of ring closing metathesis (RCM) reaction. Incidentally, the total synthesis of
gabosine H 6 was not only accomplished for the first time but the synthesis also ascertained the absolute stereochemistry of the natural product. During the course of the synthesis of gabosine A 4,
an unprecedented formation of a unique 14-membered macrocycle 7 was observed. Incisive studies were conducted to elucidate the reaction sequence for the formation of the macrocyle 7. It was found that the formation of the macrocycle 7 was through a tandem cross-metathesis/intramolecular hetero
Diels-Alder reaction. Section B of chapter 1 delineated the utility of the -hydroxy amide 3a in the total synthesis of
(–)-crassalactone C 8a. Crassalactone C 8a is a cinnamoyl derivative of styryllactone natural product goniofufurone and was found to possess marginal in vitro cytotoxic activity. Pivotal strategies in the
synthesis include the use of bis-cinnamoyl ester 10a in the ring closing metathesis reaction which also evades the selective cinnamoylation of the benzylic hydroxy group. Section C of Chapter 1 deals with the total synthesis of (+)-anamarine 11. While the - hydroxy amide 3a was employed to synthesize an important intermediate 12 enroute to the synthesis of anamarine, to mitigate the number of steps in the synthesis, the -hydroxy amide
13 was employed for the synthesis of (+)-anamarine 11. Key reactions in the total synthesis include the use of 1,3-dithiane as a surrogate for the methyl group, Brown’s allylation and ring closing metathesis. In second chapter of the thesis, formal total synthesis of iriomoteolide 3a 16 is presented.
Iriomoteolide 3a 16 is a unique 15-membered marine macrolide isolated by Tusda’s group from the Amphidinium strain HYA024, with impressive in vitro cytotoxic activity against human lymphoma cell line DG-75 (IC50 0.08 g/mL) and Raji cells (IC50 0.05 g/mL). Salient features of the synthesis
include the synthesis of the chiral aldehyde 19 from the oxazolidinone 17 and the use of -keto phosphonate 20 derived from D-(–)-tartaric acid in the Horner-Wadsworth-Emmons olefination reaction to construct the C1-C10 fragment 23 of iriomoteolide 3a 16. Synthesis of the C10-C18 fragment 29 was accomplished from the butyrolactone 24 using
Keck allylation and olefin cross metathesis reactions as key steps. Ring closing metathesis of the ester 30, followed by selective deprotection of the primary TBS group afforded the key intermediate 31,
the transformation of which to iriomoteolide 3a 16 is known in literature.
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Co(II) Based Magnetic Systems. Part I Spin Crossover Systems and Dendritic Frameworks. Part II Co(II) Single Molecule Magnets.Farghal, Ahmed M. S. January 2012 (has links)
This work comprises two main parts. The first part outlines our efforts to expand on the recent work of Gütlich et.al. by synthesizing Co(II) based spin crossover systems within a dendritic framework. We wanted to investigate the possibility of synthesizing different first generation, triazole containing dendrimers using “click” type reactions and their coordination ability with Co(II) ions. To this end we have had limited success mainly due to the numerous challenges in synthesizing a pure dendrimer product.
The second part details our efforts in the synthesis of a mononuclear Co(II) based single molecule magnet. This comes as an extension to recent reports by Chang and Long where they have successfully obtained mononuclear Fe(II) single molecule magnets by inducing structural distortions within the complexes to amplify the spin-orbit coupling. We postulated that the use of Co(II) in conjunction with a bulky ligand framework would lead to desirable magnetic properties. We chose the known bis(imino)pyridine ligand scaffold due to its rich chemistry and its interesting and unexpected coordination behaviour, as we have seen in previous research efforts by our lab. To this end we were successful in isolating and characterizing 4 compounds, and we have carried out detailed magnetic measurements on the two most magnetically interesting species.
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Nuclear Magnetic Resonance of Low-Receptivity Nuclides: The First Demonstration of 61Ni SSNMR as Applied to Structural and Crystallographic Characterization of Diamagnetic Nickel ComplexesWerhun, Peter January 2017 (has links)
Nuclear magnetic resonance (NMR) spectroscopy has proven to be an invaluable tool for the modern chemist, despite being a relatively insensitive spectroscopic technique. However, it is precisely this insensitivity that limits characterization of low-receptivity nuclides, which make up the bulk of transition metal nuclides, in particular. In this work, high-fields were used to collect the first 61Ni solid-state NMR (SSNMR) spectra of diamagnetic nickel compounds, specifically, bis(1,5-cyclooctadiene)nickel(0) (Ni(cod)2), tetrakis(triphenylphosphite)nickel(0) (Ni[P(OPh)3]4), and tetrakis(triphenylphosphine)nickel(0) (Ni(PPh3)4). This was complemented by NMR study of the co-ordinated ligands and 61Ni density functional theory (DFT) computations.
61Ni SSNMR spectra of Ni(cod)2 were used to determine its isotropic chemical shift (δiso = 965 ± 10 ppm), span (Ω = 1700 ± 50 ppm), skew (κ = -0.15 ± 0.05), quadrupolar coupling constant (CQ = 2.0 ± 0.3 MHz), quadrupolar asymmetry parameter (η = 0.5 ± 0.2), and the relative orientation of the chemical shift and EFG tensors. Solution study of Ni(cod)2 saturated in C6D6 yielded a narrow 61Ni signal, and the temperature dependence of δiso(61Ni) was assessed (δiso being 936.5 ppm at 295 K). The solution is proposed as a secondary chemical shift reference for 61Ni NMR in lieu of the extremely toxic Ni(CO)4 primary reference. For Ni[P(OPh)3]4, 61Ni SSNMR was used to infer the presence of two distinct crystallographic sites and establish ranges for δ¬iso in the solid state, as well as an upper bound for CQ (3.5 MHz for both sites). For Ni(PPh3)4, fitting provided a δiso value of 515 ± 10 ppm, Ω of 50 ± 50 ppm, κ of 0.5 ± 0.5, CQ of 0.05 ± 0.01 MHz, and η of 0.0 ± 0.2. Ni(cod)2 was chosen for study as it is a ubiquitous source of nickel(0), used for both further synthesis of nickel(0) compounds and directly as a catalyst. The study of Ni[P(OPh)3]4 and Ni(PPh3)4 demonstrated the utility of 61Ni SSNMR given the lack of a previously reported crystal structure for both and the transient nature of Ni(PPh3)4 in solution.
The work begins in Chapter 1 by introducing the interactions fundamental to NMR spectroscopy, before moving on to briefly review the field of transition metal nuclide NMR, the chemistry of nickel (with an emphasis on homogeneous catalysis with nickel(0)), and the literature with respect to nickel NMR up to this point. In Chapter 2, the theory and practice of NMR are explained, including solid-state NMR, as well as the basic principles of density functional theory NMR computations. The specific experimental and computational methods of this work are also introduced. Lastly, in Chapter 3 the results are discussed in the context of the concepts presented and literature reviewed, and highlight the use of 61Ni NMR as a means to gain novel information about the chemistry of the compounds studied.
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Vývoj zahraničního zadlužení zemí východního rozšíření EU (90. léta až současnost) / The external debt development of the transitive countries attended to the east expansion of EUBokrová, Lenka January 2007 (has links)
The external debt is no doubt "a front burner" nowadays, not only in the group of well informed economists or politicians. And although it is regarded as a problem ascribed to the third world countries only, any national economy can bear it. Anyway, neither developed countries are exceptions, despite distinctly small attention which is given to them from the external indebtedness point of view. In my thesis, I decided to link the foreign debt problem with another frequent topic of any discussions: with the really prudent process of the European Union expansion to the East. Primarily, I will try to confute many skewed information about both of them. Or - is the foreign debt really such an uncompromising indicator of the external instability hindering any economic progress? Must thus the relatively successful transformation of the transitive economies pass off with the zero foreign indebtedness entirely?
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Influência da alteração do pH e da degradação enzimática na rugosidade das superfícies de resinas compostas / Influence of change of pH and enzymatic degradation in the roughness of the surfaces of composite resinsSalgado, Lívia 27 April 2015 (has links)
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Previous issue date: 2015-04-27 / FAPEMIG - Fundação de Amparo à Pesquisa do Estado de Minas Gerais / Avaliou-se a rugosidade das superfícies de duas resinas compostas, antes e após a sua imersão em solução aquosa com diferentes pH e solução enzimática. Para a confecção dos 60 corpos de prova, 30 para cada resina composta, utilizou-se uma matriz de acrílico com 5mm de diâmetro e 2mm de espessura, sobre uma tira de poliéster posicionada em uma placa de vidro estéril que foram preenchidas com as resinas compostas Filtek Z350 (3M ESPE) e Empress Direct (Ivoclar-Vivadent), em um único incremento e sobre esta foi colocada outra tira de poliéster e procedeu a fotopolimerização por 40s. Os corpos de prova foram divididos 06 grupos (n=10) de acordo com a solução empregada: água deionizada (Grupos ZA e EA); hidróxido de sódio com pH 13.2 (Grupos ZNa e ENa) e solução enzimática de colesterol esterase (Grupos ZE e EE). Para dar acabamento utilizou-se uma sequência decrescente de granulação de lixas d’água: 600, 1000, 1200, 1500 e 2000 e para o polimento, suspensões de alumina (Arotec, São Paulo, SP, Brasi): 1μm, 0,3μm e 0,05μm. Após o polimento foram armazenados em estufa a 37°C durante 7 dias e realizadas 3 medições de cada superfície no rugosímetro e realizada a média e foram imersos individualmente nas soluções por 30 dias e mantidos em estufa a 37°C, a cada 7 dias as soluções eram trocadas. Após 30 dias foram realizadas mais 3 medições da rugosidade das superfícies e realizada a média. Foi realizada ANOVA e o teste de Tukey. A partir dos resultados obtidos conclui-se que as resinas compostas testadas apresentaram degradação hidrolítica apenas na solução aquosa por um período de imersão de 30 dias. / The roughness of the surfaces was evaluated two composites before and after their immersion in aqueous solutions with different pH and the enzyme solution. For producing the 60 test specimens, 30 for each composite was used an acrylic matrix with 5mm in diameter and 2mm thick on a polyester strip placed on a sterile glass plate were filled with the resins Filtek Z350 (3M ESPE) and Empress Direct (Ivoclar Vivadent-) in a single increment and this was placed on another strip of polyester and proceeded to light curing for 40 seconds. The specimens were divided 06 groups (n = 10) according to the used solution: deionized water (ZA Groups and EA); sodium hydroxide at pH 13.2 (ZNA Groups ENA) and enzyme solution of cholesterol esterase (ZE and EE groups). To finish used a descending sequence of sanding granulation water: 600, 1000, 1200, 1500 and 2000 and for polishing alumina suspensions (Arotec, São Paulo, SP, Brasi): 1μm, and 0,3μm 0,05μm. After polishing were stored at 37 ° C for 7 days and 3 measurements carried out on each surface roughness and the carried medium and were immersed in individual solutions and kept for 30 days at 37 ° C every 7 days the solutions were exchanged. After 30 days there were over 3 measurements of surface roughness and made average. ANOVA and Tukey test was performed. From the results obtained it is concluded that the composites tested showed hydrolytic degradation in aqueous solution only for a period of 30 days immersion.
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Die Architekturornamentik des Jupitertempels in BaalbekWienholz, Holger 08 October 2020 (has links)
Der Bauschmuck des Jupitertempels in Baalbek ist durch sechs noch stehende
Säulen mitsamt Gebälk sowie durch zahlreiche im Gelände verstreute Fragmente
bezeugt. Durch die hier vorliegenden Untersuchungen konnten nun erstmals auch
Fragmente nachgewiesen werden, die zum Aufbau der ansonsten verlorenen
Tempelcella gehörten.
Über eine möglichst umfassende Katalogisierung konnte der Materialbestand weit
über das bisher bekannte Maße gesichert werden, so daß zum Beispiel mit 23 statt
der in der Forschung bisher üblichen 2 Kapitelle gearbeitet werden konnte.
Der Fokus der Arbeit liegt zunächst auf der Darstellung und Beschreibung des
Tempels sowie seiner kulturellen und bauhistorischen Verortung in Baalbek
selbst. Als feste Referenzpunkte außerhalb der Stadt wurden der Mars-Ultor-
Tempel in Rom sowie der Bel-Tempel von Palmyra gewählt. Durch diese
Vergleiche und durch einen erstmals in der Forschungsgeschichte
vorgenommenen Vergleich der einzelnen Ornamentzonen untereinander konnte
eine neue Datierung vorgenommen werden, wodurch der Aufbau und die
Fertigstellung des Baus in die 2. Hälfte des 1. Jhs. n. Chr. zu rücken sind.
Die Interpretation der Architekturornamentik führte zu mehreren, zum Teil völlig
neuen Ergebnisse. Der große und schon vielfach bemerkte Reichtum in der
Ausarbeitung des Bauschmucks zeigt das große Können, ein umfangreiches
Repertoire und vor allem eine große Freiheit der ausführenden Steinmetzen, die
wohl eher lokaler Abstammung waren.
Darüber hinaus ist der extra für den Tempel entworfene Fries eine politische
Aussage der Colonia Beirut/Heliopolis, mit dem die neu erworbene Stellung im
Machtgefüge der levantinischen Städte demonstriert werden soll.
Die immer wieder auftretende Unfertigkeit bei der Fertigstellung der Ornamentik
ist systematisch und läßt sich mit den umfassenden finanziellen Problemen im
römischen Steuerwesen beim Übergang zwischen der neronischen und der
flavischen Epoche begründen. / The architectural decoration of the temple of Jupiter in Baalbek is testified by six
still standing columns with their entablature and numerous fragments in the area
around. This study presents for the first time also fragments from the construction
of the otherwise lost cella of the temple.
By building a nearly complete catalog of the fragments it was possible to secure
the material stock far beyond it was known by now, so for example it was possible
to work with 23 instead of the 2 capitals that had been used in former research.
The mainly focus of the work is on the representation and description of the
temple and its cultural and architectural location in the city of Baalbek. The
temple of Mars-Ultor in Rome and the temple of Bel in Palmyra were chosen as
fixed reference points. Through these comparisons and through a comparison of
the individual ornamental zones with each other for the first time in the history of
research, a new dating could be established, which places the construction and
completion of the building in the 2nd half of the 1st century AD.
The interpretation of architectural ornamentation led to several completely new
results. The great and already noticed wealth in the elaboration of architectural
ornamentation shows the great skill, an extensive repertoire and above all a great
freedom of the executing stonemasons, who were probably of more local origin.
Furthermore the frieze was specially designed for the temple and is a political
statement of the Colonia Beirut/Heliopolis, which is intended to demonstrate the
newly acquired position in the administratic structure of the Levantine cities.
The recurrent incompleteness in the ornamentation is systematic and can be
explained by the financial problems in the roman state finances during the
transition between the Neronic and Flavian eras.The architectural decoration of the temple of Jupiter in Baalbek is testified by six
still standing columns with their entablature and numerous fragments in the area
around. This study presents for the first time also fragments from the construction
of the otherwise lost cella of the temple.
By building a nearly complete catalog of the fragments it was possible to secure
the material stock far beyond it was known by now, so for example it was possible
to work with 23 instead of the 2 capitals that had been used in former research.
The mainly focus of the work is on the representation and description of the
temple and its cultural and architectural location in the city of Baalbek. The
temple of Mars-Ultor in Rome and the temple of Bel in Palmyra were chosen as
fixed reference points. Through these comparisons and through a comparison of
the individual ornamental zones with each other for the first time in the history of
research, a new dating could be established, which places the construction and
completion of the building in the 2nd half of the 1st century AD.
The interpretation of architectural ornamentation led to several completely new
results. The great and already noticed wealth in the elaboration of architectural
ornamentation shows the great skill, an extensive repertoire and above all a great
freedom of the executing stonemasons, who were probably of more local origin.
Furthermore the frieze was specially designed for the temple and is a political
statement of the Colonia Beirut/Heliopolis, which is intended to demonstrate the
newly acquired position in the administratic structure of the Levantine cities.
The recurrent incompleteness in the ornamentation is systematic and can be
explained by the financial problems in the roman state finances during the
transition between the Neronic and Flavian eras.
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Synthèse et caractérisation de poly(aryl éther cétone amide)s / Synthesis and characterization of poly(aryl ether ketone amide)sOsegueda, Juan 16 December 2016 (has links)
Certaines applications (notamment dans l'aéronautique) demandent des polymères thermostables semi-cristallins avec des résistances et des températures de fonctionnement de plus en plus élevées (Tg supérieures à 170°C) tout en conservant de bonnes propriétés de mise en œuvre (Tf ne dépassant pas 350°C) aptes aux procédés industriels. Ce projet de thèse porte sur la synthèse et la caractérisation de nouveaux polymères hautes performances de type poly(aryl éther cétone amide)s à partir d'un monomère de type EKKE aux extrémités acide carboxylique. Ainsi, trois voies de synthèse des amides par condensation ont été étudiées : entre les acides carboxyliques et les isocyanates, entre les chlorures d'acyle et les amines, et entre les acides carboxyliques et les amines par phosphorylation. La comparaison des propriétés thermiques et leurs corrélations avec les structures chimiques des poly(aryl éther cétone amide)s aromatiques et semi-aromatiques obtenus sont particulièrement détaillées. / Some demanding applications (especially in aerospace) require more and more semi-crystalline thermostable polymers with high temperature resistance and durability (Tg above 170 °C) while maintaining good processing properties (Tm not exceeding 350°C) suitable for industrial manufacturing.This work deals with the synthesis and characterization of new high performance poly(aryl ether ketone amide)s polymers from an EKKE monomer with carboxylic acid extremities. Thus, three amide condensation synthetic routes were studied: between carboxylic acids and isocyanates, between acyl chlorides and amines, and between carboxylic acids and amines by phosphorylation. The thermal properties and their correlation with the chemical structures of the obtained aromatic and semi-aromatic poly(aryl ether ketone amide)s are compared and especially detailed.
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Di-(2-Ethylhexyl)-Phthalate (DEHP) Causes Impaired Adipocyte Function and Alters Serum MetabolitesKlöting, Nora, Hesselbarth, Nico, Gericke, Martin, Kunath, Anne, Biemann, Ronald, Chakaroun, Rima, Kosacka, Joanna, Kovacs, Peter, Kern, Matthias, Stumvoll, Michael, Fischer, Bernd, Rolle-Kampczyk, Ulrike, Feltens, Ralph, Otto, Wolfgang, Wissenbach, Dirk K., von Bergen, Martin, Blüher, Matthias January 2015 (has links)
Di-(2-ethylhexyl)-phthalate (DEHP), an ubiquitous environmental contaminant, has been shown to cause adverse effects on glucose homeostasis and insulin sensitivity in epidemiological studies, but the underlying mechanisms are still unknown. We therefore tested the
hypothesis that chronic DEHP exposure causes impaired insulin sensitivity, affects body weight, adipose tissue (AT) function and circulating metabolic parameters of obesity resistant 129S6 mice in vivo. An obesity-resistant mouse model was chosen to reduce a potential obesity bias of DEHP effects on metabolic parameters and AT function. The metabolic
effects of 10-weeks exposure to DEHP were tested by insulin tolerance tests and quantitative assessment of 183 metabolites in mice. Furthermore, 3T3-L1 cells were cultured with DEHP for two days, differentiated into mature adipocytes in which the effects on insulin
stimulated glucose and palmitate uptake, lipid content as well as on mRNA/protein expression of key adipocyte genes were investigated.We observed in female mice that DEHP treatment causes enhanced weight gain, fat mass, impaired insulin tolerance, changes in circulating adiponectin and adipose tissue Pparg, adiponectin and estrogen expression. Serum metabolomics indicated a general increase in phospholipid and carnitine concentrations. In vitro, DEHP treatment increases the proliferation rate and alters glucose uptake in adipocytes. Taken together, DEHP has significant effects on adipose tissue (AT) function and alters specific serum metabolites. Although, DEHP treatment led to significantly impaired insulin tolerance, it did not affect glucose tolerance, HOMA-IR, fasting glucose, insulin or triglyceride serum concentrations. This may suggest that DEHP treatment does not cause impaired glucose metabolism at the whole body level.
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Synthesis of bis(oxamato) transition metal complexes and Ni nanoparticles and their structural, magnetic, optical, and magneto-optical characterizationBräuer, Björn 02 July 2008 (has links)
Im Rahmen dieser Arbeit werden ein- und mehrkernige Cu(II)- und Ni(II)-bis(oxamato)-Komplexe im Hinblick auf ihre magneto-optischen Eigenschaften gezielt hergestellt und strukturell charakterisiert. Über ladungs- und übergangsmetallinduzierte Abweichungen vom allgemeinen in der Literatur beschriebenen Reaktionsverhalten wird berichtet.
Aus Elektronenspinresonanz-Untersuchungen wird die Spindichteverteilung in den einkernigen Cu(II)-Komplexen abgeleitet. Die Beeinflussung dieser durch die Koordinationsgeometrie sowie die Auswirkungen auf die Superaustausch-Wechselwirkung werden diskutiert und mit Ergebnissen der Dichtefunktionaltheorie (DFT) verglichen. Dreikernige bis(oxamato)-Komplexe werden erstmals durch Spin-Coating auf Si(111)-Substraten aufgebracht und mit Hilfe der spektroskopischen Ellipsometrie sowie der Ramanspektroskopie untersucht und mittels DFT-Berechnungen ausgewertet. Magneto-optische Kerr-Effekt-Untersuchungen werden an dünnen Schichten dieser Komplexe sowie Phthalocyaninen durchgeführt.
Zum Vergleich werden die magnetischen und magneto-optischen Eigenschaften von Ni-Nanopartikeln in verschiedenen organischen Matrizen untersucht. Mit Hilfe der Photoelektronenspektroskopie wird das Oxidationsverhalten dieser studiert und es werden Rückschlüsse auf Ladungstransferprozesse zwischen den Matrizen und den Nanopartikeln gezogen.
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